1. Field of the Invention
The present invention relates to an optical semiconductor lighting apparatus. More particularly, the invention relates to an optical semiconductor lighting apparatus operable to be disposed in a workplace having air entrained particulates, to generate ambient light.
2. Discussion of the Background
Artificial light sources employed in lighting devices include an incandescent lamp, fluorescent lamp, etc. More recently, a light emitting diode (LED) element has been successfully employed as a light source. The LED element has many desirable advantages such as luminous efficiency, low power consumption, ecological friendliness, etc. Lighting apparatus including an LED element may be used for an indoor lamps in a home or office, or in a more industrial environment such as in an industrial workplace where automobiles are being assembled, iron smelting is occurring, textile sewing operations are taking place, etc. However, in many industrial plants dust, air entrained particulates or foreign substances may exist which may penetrate into a lighting to cause failure or inefficient operation of the lighting apparatus, or may be deposited on the surface of the lighting apparatus which tend to reduce luminous efficiency and heat dissipation efficiency. In addition, dust, air entrained particulates, foreign substances, etc. may stick to a reflector of a lighting fixture, to reduce reflection efficiency and heat dissipation efficiency of the reflector or as a minimum damage the appearance of the fixture.
Especially, in instances of a workplace environment with high ambient temperatures such as in iron production, for example, heated air rises and dust, air entrained particulates or foreign substances are born along with an ascending air current and can be deposited on a lighting element, a reflector, etc. of a lighting fixture. Therefore, in order to prevent an accumulation of the dust, air entrained particulates, and other foreign substances it is a conventional maintenance requirement that a worker routinely clean lighting fixtures.